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Publications

USGS research activities relevant to Alaska have yielded more than 9400 historical publications. This page features some of the most recent newsworthy research findings.

Filter Total Items: 3087

Remigial molt of sea ducks Remigial molt of sea ducks

Molt is a dynamic process occurring throughout much of the year in waterfowl. The molt of flight feathers by waterfowl, especially sea ducks, however, occurs over a compressed period of time and in spcific areas used each year. We provide an overview of the flight feather molt of sea ducks. We focus on the need to molt and why, the timing and duration of flight feather mot, and the...
Authors
Margaret R. Petersen, Jean-Pierre L. Savard

Population dynamics of sea ducks: using models to understand the causes, consequences, evolution, and management of variation in life history characteristics Population dynamics of sea ducks: using models to understand the causes, consequences, evolution, and management of variation in life history characteristics

In this chapter, I explore population dynamics of sea ducks by developing population models. In determining which life history characteristics had the greatest influence on future population dynamics, adult female survival consistently had the highest sensitivity and elasticity and this result was robust across a wide range of life history parameter values. Conversely, retrospective...
Authors
Paul L. Flint

Habitats of North American sea ducks. Habitats of North American sea ducks.

Breeding, molting, fall and spring staging, and wintering habitats of the sea duck tribe Mergini are described based on geographic locations and distribution in North America, geomorphology, vegetation and soil types, and fresh water and marine characteristics. The dynamics of habitats are discussed in light of natural and anthropogenic events that shape areas important to sea ducks...
Authors
Dirk V. Derksen, Margaret R. Petersen, Jean-Pierre L. Savard

Variation in migration strategies of North American sea ducks Variation in migration strategies of North American sea ducks

Migration exerts strong effects on population dynamics, so consideration of migration as a driver of population change is an important area of inquiry. Sea ducks (Mergini) exemplify the wide range in types of migration strategies, which become more variable with the addition of a third migration to distinct molting areas. We discuss the three migrations, summer, fall, and molt, and...
Authors
Margaret R. Petersen, Jean-Pierre L. Savard

Diet of yellow-billed loons (Gavia adamsii) in Arctic lakes during the nesting season inferred from fatty acid analysis Diet of yellow-billed loons (Gavia adamsii) in Arctic lakes during the nesting season inferred from fatty acid analysis

Understanding the dietary habits of yellow-billed loons (Gavia adamsii) can give important insights into their ecology, however, studying the diet of loons is difficult when direct observation or specimen collection is impractical. We investigate the diet of yellow-billed loons nesting on the Arctic Coastal Plain of Alaska using quantitative fatty acid signature analysis. Tissue analysis...
Authors
T B Haynes, Joel A. Schmutz, Jeffrey F. Bromaghin, S J Iverson, V. M. Padula, A E Rosenberger

Can polar bears use terrestrial foods to offset lost ice-based hunting opportunities? Can polar bears use terrestrial foods to offset lost ice-based hunting opportunities?

Increased land use by polar bears (Ursus maritimus) due to climate-change-induced reduction of their sea-ice habitat illustrates the impact of climate change on species distributions and the difficulty of conserving a large, highly specialized carnivore in the face of this global threat. Some authors have suggested that terrestrial food consumption by polar bears will help them withstand...
Authors
Karyn D. Rode, Charles T. Robbins, Lynne Nelson, Steven C. Amstrup

Prevalence and genetic diversity of haematozoa in South American waterfowl and evidence for intercontinental redistribution of parasites by migratory birds Prevalence and genetic diversity of haematozoa in South American waterfowl and evidence for intercontinental redistribution of parasites by migratory birds

To understand the role of migratory birds in the movement and transmission of haematozoa within and between continental regions, we examined 804 blood samples collected from eleven endemic species of South American waterfowl in Peru and Argentina for infection by Haemoproteus, Plasmodium, and/or Leucocytozono blood parasites. Infections were detected in 25 individuals of six species for...
Authors
Matthew M. Smith, Andrew M. Ramey

A real-time, quantitative PCR protocol for assessing the relative parasitemia of Leucocytozoon in waterfowl A real-time, quantitative PCR protocol for assessing the relative parasitemia of Leucocytozoon in waterfowl

Microscopic examination of blood smears can be effective at diagnosing and quantifying hematozoa infections. However, this method requires highly trained observers, is time consuming, and may be inaccurate for detection of infections at low levels of parasitemia. To develop a molecular methodology for identifying and quantifying Leucocytozoon parasite infection in wild waterfowl...
Authors
Matthew M. Smith, Joel A. Schmutz, Chloe Apelgren, Andrew M. Ramey

Reconnaissance investigation of the Lisburne Group in the Cobblestone Creek area, Chandler Lake quadrangle, Alaska Reconnaissance investigation of the Lisburne Group in the Cobblestone Creek area, Chandler Lake quadrangle, Alaska

A reconnaissance investigation of the Carboniferous Lisburne Group in the Cobblestone Creek area, Chandler Lake Quadrangle, yields insights into its resource potential and regional relations. Locally porous vuggy dolostone with hydrocarbon reservoir potential occurs in the lower Lisburne in the three most southerly of five thrust sheets, and contains traces of dead oil in two of these...
Authors
Julie A. Dumoulin, Michael T. Whalen

Diverse juvenile life-history behaviours contribute to the spawning stock of an anadromous fish population Diverse juvenile life-history behaviours contribute to the spawning stock of an anadromous fish population

Habitat quality often varies substantially across space and time, producing a shifting mosaic of growth and mortality trade-offs across watersheds. Traditional studies of juvenile habitat use have emphasised the evolution of single optimal strategies that maximise recruitment to adulthood and eventual fitness. However, linking the distribution of individual behaviours that contribute to
Authors
Timothy E. Walsworth, Daniel E. Schindler, Jennifer R. Griffiths, Christian E. Zimmerman

Sampling of sea ducks for influenza A viruses in Alaska during winter provides lack of evidence for epidemiological peak of infection. Sampling of sea ducks for influenza A viruses in Alaska during winter provides lack of evidence for epidemiological peak of infection.

Sampling of sea ducks for influenza A viruses in Alaska during winter provided no evidence for an epidemiologic peak of infection. Isolates were recovered, however, that provide information on viral diversity and dispersal that may not be realized through sampling efforts focused on other avian taxa.
Authors
Andrew M. Ramey, Andrew B. Reeves, Rebecca L. Poulson, Jeff Wasley, Daniel Esler, David E. Stalknecht

Evidence for the assimilation of ancient glacier organic carbon in a proglacial stream food web Evidence for the assimilation of ancient glacier organic carbon in a proglacial stream food web

We used natural abundance δ13C, δ15N, and Δ14C to compare trophic linkages between potential carbon sources (leaf litter, epilithic biofilm, and particulate organic matter) and consumers (aquatic macroinvertebrates and fish) in a nonglacial stream and two reaches of the heavily glaciated Herbert River. We tested the hypothesis that proglacial stream food webs are sustained by organic...
Authors
Jason Fellman, Eran Hood, Peter A. Raymond, J.H. Hudson, Maura Bozeman, Mayumi L. Arimitsu
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